1859-1863] METAMORPHOSIS 233 



about poverty of fresh-water is very true. 1 I think you might Letter 158 

 write a memoir on fresh-water productions. I suggest that 

 the key-note is that land-productions are higher and have 

 advantage in general over marine ; and consequently land- 

 productions have generally been modified into fresh-water 

 productions, instead of marine productions being directly 

 changed into fresh-water productions, as at first seems more 

 probable, as the chance of immigration is always open from 

 sea to rivers and ponds. 



My talk with you did me a deal of good, and I enjoyed it much. 



Letter 159 



To J. D. Hooker. 



Down, Jan. 13th [1863]. 



I send a very imperfect answer to [your] question, 



which I have written on foreign paper to save you copying, 



and you can send when you write to Thomson in Calcutta. 



Hereafter I shall be able to answer better your question 



about qualities induced in individuals being inherited ; gout 



in man — loss of wool in sheep (which begins in the first 



generation and takes two or three to complete) ; probably 



obesity (for it is rare with poor) ; probably obesity and 



early maturity in short-horn cattle, etc., etc. 



Letter 160 



To A. De Candollc. 2 



Down, Jan. 14th [1863]. 



I thank you most sincerely for sending me your Memoir. 3 

 I have read it with the liveliest interest, as is natural for me ; 



1 " We cannot but be struck by the poverty of the fresh-water fauna 

 when compared with that of the ocean " (op. at., p. 64). 



2 Alphonse Louis Pierre Pyramus De Candolle (1806-93) was tne 

 son of Augustin Pyramus, and succeeded his father as Professor of 

 Botany at Geneva in 1835. He resigned his Chair in 1850, and devoted 

 himself to research for the rest of his life. At the time of his father's 

 death, in 1841, seven volumes of the Prodromus had appeared : Alphonse 

 completed the seventeenth volume in 1873. In 1855 appeared his Gco- 

 grapliie botatrique raisonm'e, " which was the most important work of his 

 life," and if not a precursor, " yet one of the inevitable foundation-stones " 

 of modern evolutionary principles. He also wrote Histoirc des Savants, 

 1873, an d Phytographie, 1880. He was lavish of assistance to workers in 

 Botany, and was distinguished by a dignified and charming personality. 

 (See Sir W. Thiselton-Dyer's obituary in Nature, July 20th, 1893, p. 269.) 



3 Etude sur l'Espece a l'occasion d'une revision dc la Famille des 

 Cupuliferes. Biblioth. Univ. {Arch, des Sc. Phys. ct Nat.), Novembre 1862. 



